Prosecutors filed papers today for permission to use a cellphone Figueroa's wife, Sonia Panell, allegedly smuggled to him in prison. Police say the phone was used to help make arrangements to kill the witnesses.

Figueroa remains in prison without bail, charged with killing 23-year old Yolanda Morales during a December 2012 gunbattle. Bail in the murder-for-hire case was set at $500,000.

According to court records, Martin is cooperating with authorities.

Court papers say Figueroa was unable to get Martin released from prison.

When that plan failed, Panell unwittingly told an FBI informant she would supply the person with a vehicle, handgun and night-vision goggles to conduct surveillance before killing Oralis Figueroa, Hungerford and a third witness, Angel Figueroa, police say.

In early 2014, Figueroa warned Panell to get "out of the middle" of the plan, and he wanted her to have the goggles delivered directly to the hit man, court records say. Panell was relaying information to Figueroa then about the target's activities gleaned from Facebook updates, court records say.

Panell's federal charges were made public Feb. 21; she and her husband have since been charged in connection with smuggling the cellphone into the county prison.